Infrared multiple photon dissociation spectroscopy of anionic copper formate clusters
Tobias F Pascher1, Milan Ončák1, Christian van der Linde1
1Institut für Ionen und Angewandte Physik, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
The Journal of Chemical Physics
|November 14, 2020
Summary
Investigating copper formate clusters reveals how formate ligands bind to copper. Deuteration confirms Fermi interactions and shows C-D stretching shifts depend on copper
Area of Science:
- Physical Chemistry
- Materials Science
- Spectroscopy
Background:
- Understanding the structure and bonding of metal-organic clusters is crucial for catalysis and materials design.
- Copper formate clusters serve as model systems for studying formate interactions with copper surfaces.
Purpose of the Study:
- To elucidate the structural properties of copper formate and deuterated copper formate clusters.
- To characterize vibrational modes and identify binding motifs of formate ligands.
- To investigate the influence of cluster structure and copper oxidation state on vibrational spectra.
Main Methods:
- Infrared multiple photon dissociation (IRMPD) spectroscopy was employed to probe cluster vibrations.
- Quantum chemical calculations were utilized to interpret experimental spectra and explore potential energy surfaces.
- Deuteration of copper formate was used to confirm vibrational assignments and study Fermi resonance effects.
Main Results:
- Vibrational spectra show a strong dependence on monodentate versus bidentate formate binding.
- Fermi interactions involving C-H stretching modes were confirmed through deuteration.
- C-D stretching frequencies exhibit characteristic shifts related to binding motifs and copper oxidation state.
Conclusions:
- The binding motif of formate ligands significantly influences the vibrational spectra of copper formate clusters.
- Deuteration provides a clear spectral window for analyzing formate binding and copper oxidation state effects.
- Spectroscopic data offer insights comparable to formate adsorption on copper surfaces.
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